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Full text of "Alaskan glacier studies of the National Geographic Society in the Yakutat Bay, Prince William Sound and lower Copper River regions"

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364                                 ALASKAN GLACIER STUDIES
the valley has a tolerably even surface, and was nearly destitute of any vegetable productions, and was equally passable in all directions. Its situation and character corresponded also with the description of it given by the Russians, and Mr. Whidbey's mensuration agreed nearly with the distance across as stated by them, namely, about sixteen versts."
Before 1880 when Petroff made journeys in this part of Alaska while taking the census, and 1887 when Applegate visited the head of Passage Canal, the Portage Glacier had apparently advanced and occupied Whidbey's "valley of some breadth," which contained "elevated land," and was "very free from snow and appeared to be perfectly easy of access," leaving a "tolerably even surface," "nearly destitute of any vegetable productions," and "equally passable in all directions." Petroff's description indicates; that a great glacial advance had taken place, for he states that a "glacial formation forms the portage route between Chugatch bay1 and Cook's Inlet"; and he shows the glacier on his map of 1880, much as at present. Applegate's map, based upon a close observation from his schooner in June, 1887, has the Portage Glacier joining the one from the north and ending on the land just west of the head of Passage Canal.
Although admitting a reasonable doubt that Whidbey may not have known a valley glacier when he saw one, we feel rather certain that a great advance had taken place. It is clear that the portage route used by the natives and the Russians was not the non-glacial route traversed by army parties in 1898 and 1899, although this starts from near the Russian house at the mouth of Cabin Creek on the delta of the stream from Billings Glacier. This seems certain because (a) this route is too long, and (b) within 1$ miles of Cabin Creek it goes over a 8000-foot, snow-covered pass. Such a route could not have been traversed habitually by the natives, taking their canoes with them; and that this was the case at the time of Whidbey's exploration, is indicated by Vancouver's statement that in 1794 Lieutenant Johnstone encountered some strange natives in eastern Prince William Sound and "clearly understood that the strangers had come immediately from Groosgincloose, or Cook's Inlet, and that they * with their canoes, had crossed the isthmus overland that separates this sound from Turn-again Arm"
Neither does it seem probable that the natives carried canoes over the Portage Glacier as at present, for it ascends so steeply east of the divide that in 1898 the prospectors had to use ropes and pulleys in drawing their sleds up over the last ascent. Moreover, Alaskan natives are notoriously timid about trusting themselves on glaciers. None of Vancouver's maps show glaciers, even where they existed, but they are usually mentioned, so that we feel quite confident that in 1794 there was no Portage Glacier of anything like the present dimensions. Judging by his other descriptions, Whidbey would not have described, in the language quoted, a valley that contained a glacier with an ascent in the first mile to over 1000 feet, and with the terminus only three-quarters of a mile from the coast where he stood.
It therefore appears probable that before 1794 the through valley in which Portage Glacier now lies was free from glacier ice, though the tributary glaciers doubtless existed as separate ice tongues. If this interpretation of the discrepancy between present conditions and earlier descriptions is correct, there has occurred here between 1794
1 An old name for Prince William Sound. * The italics are Vancouver's.